Image Cropping Manipulation Method and Portable Electronic Device

ABSTRACT

The invention discloses an image cropping manipulation method for use in a portable electronic device. The portable electronic device comprises a touch screen and an image processing unit. The method comprises: displaying a sub-image on the touch screen, the sub-image is cropped from a digital image; receiving a user input from the touch screen; in response to the user input, map the user input to an operation on the digital image; and performing the operation to update the sub-image.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image cropping manipulation methodand a portable electronic device thereof, and more particularly, acropping manipulation method for updating content of a cropped imageaccording to user inputs.

2. Description of the Prior Art

Image cropping is one of the image editing tools often used by user.Conventionally, image cropping applications provide a cropping frame ofcertain shape, such as rectangular, circle or heart shape, etc. and usermay move the cropping frame to desired position within the image andadjust the size of the cropping frame. The image cropping applicationwould crop a sub-image according to the cropping frame and store thesub-image for other use. For example, the sub-image may be stored as aseparate image, integrated with other images or image templates. Thoughthe position and the size of the cropping frame can be designated byuser, the respective shape and image distortion cannot be solved byimage cropping application. For example, if an image comprising anobject is taken in a non-front view angle, the shape of the objectappears in the digital image would be distorted. For example, an objectin rectangular shape might become in trapezoid shape, another object inround shape might become in elliptical. When cropping the object fromthe digital image, the distortion caused by the inclination will also bereflected in the cropped sub-image. This would cause inconvenient oruncomfortable viewing to the user, particularly in the case that thesub-image comprises text or other useful information. Fixing thedistortion caused by viewing angle would be beneficial and improve imagequality.

To solve above issues, the present invention provides a novel approachto manipulate image viewing angle and adjust distortion caused thereof.

SUMMARY OF THE INVENTION

In an embodiment of the invention, a portable electronic device forperforming image cropping manipulation is disclosed. The portableelectronic device comprises: a touch screen configured to display asub-image and to provide a user interface for receiving at least oneuser input, the sub-image is cropped from a digital image; and an imageprocessing unit configured to perform an operation corresponding to theuser input. The image processing unit comprises: a space mapping module,configured to map the sub-image to an image space and map the user inputto the operation in the image space; and an image cropping module,configured to perform the operation and update the sub-image accordingto the user input.

In another embodiment of the invention, an image cropping manipulationmethod for use in a portable electronic device is disclosed. Theportable electronic device comprises a touch screen and an imageprocessing unit, and the method comprises: displaying a sub-image on thetouch screen, the sub-image is cropped from a digital image; receiving auser input from the touch screen; in response to the user input, map theuser input to an operation on the digital image; and performing theoperation to update the sub-image.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an image cropping manipulation for cropping asub-region from a digital image according to one embodiment of thepresent invention.

FIG. 2 illustrates a portable electronic device for implementing theimage cropping manipulation method according to one embodiment of thepresent invention.

FIGS. 3-11 illustrate embodiments of image cropping manipulation of theinvention in image space and cropping space and mapping mechanisms ofthe two spaces.

FIG. 12-13 illustrate image cropping manipulation methods according toembodiments of the present invention.

DETAILED DESCRIPTION

To solve the problem addressed above, the present invention discloses animage cropping manipulation method and a portable electronic deviceimplementing the image cropping manipulation method. In the disclosedimage cropping manipulation method, a plurality of control pointscorresponding to a sub-region within a digital image are defined andadjusted in an image space, and a sub-image corresponding to thesub-region is determined and cropped from the digital image according tothe control points.

Please refer to FIG. 1, which schematically illustrates an embodiment ofimage cropping manipulation. The image cropping manipulation may beperformed on a mobile electronic device, such as a smart phone ortablet, and the mobile electronic device may comprise a touch screen anda camera. As shown in FIG. 1, a digital image I1 is retrieved andprovided to a user. The digital image I1 can be captured by the cameraand displayed on the touch screen. The digital image I1 can also beaccessed from an internal storage unit, external storage device, orwirelessly from another data source, such as social service provider.The mobile electronic device may provide a user interface on the touchscreen for user to perform operations on digital image I1. Inembodiments of the invention, the user interface provides an imagecropping function for user to crop a sub-image C1 from the digital imageI1. The resulting sub-image C1 is displayed and can be further stored asa single image. Prior to storing the sub-image C1, user may send inputsto modify the sub-image C1 via the touch screen. For example, user mayedit content of the sub-image C1. As shown in the embodiment of FIG. 1,the digital image I1 comprises an object M, which is a painting board.Each of the corners B1˜B4 of the sub-image corresponds to one of thecontrol points A1˜A4 in the digital image I1 respectively. To generatethe sub-image C1, a sub-region R1 defined by the control points A1˜A4 iscropped from the digital image I1. The sub-image C1 may be properlyscaled to desired resolution, such as full resolution. When usermanipulates on the sub-image C1, position of corresponding controlpoints A1˜A4 would be updated accordingly, and consequently the contentof the sub-image C1 is updated.

FIG. 2 illustrates a portable electronic device 10 for performing imagecropping manipulation according to an embodiment of the invention. Theportable electronic device 10 comprises, among other components, a touchscreen 100, an image processing unit 200, a camera module 300 and astorage unit 400. The touch screen 100 is configured to display digitalimages and provide a user interface for receiving user inputs. The touchscreen 100 further comprises touch panel 110 for receiving the userinputs and a display module 120 for displaying digital images and userinterfaces. The image processing unit 200 is configured to accessdigital images and to perform various processing on the digital images.Digital images can be accessed from various image sources, such as thecamera module 300 and/or the storage unit 400. Furthermore, the imageprocessing unit 200 is configured to receive user inputs from the touchscreen 100 and perform operations corresponding to the user inputs onthe digital images. The processed digital images may be provided back tothe touch screen 100 for display and/or be stored in the storage unit400.

The image processing unit 200 further comprises at least a space mappingmodule 210 and an image cropping module 220. The space mapping module210 is configured to define an image space and a cropping space, andconvert user inputs received in one space to another. The image croppingmodule 220 is configured to crop a sub-region of a digital imageaccording to the user input and provide a sub-image corresponding to thesub-region. The image cropping module 220 is further configured toadjust pixel values and/or positions in the sub-image according to theuser input.

Described in more details with reference to FIG. 1, the touch screen 100displays the digital image I1 and receives a user input for cropping asub-region R1 from the digital image I1. Upon receiving the user input,the touch screen 100 may transmit the user input to the image processingunit 200. The space mapping module 210 may determine the position of thesub-region R1 in the digital image I1, and the image cropping module 210crops and provides a corresponding sub-image C1. The sub-image C1 isthen transmitted to the touch screen 100 for displaying to the user. Asshown in FIG. 1, the space mapping module 210 defines an image spacecorresponding to the digital image I1 and a cropping space correspondingto the sub-image C1. The sub-region R1 is defined by four control pointsA1˜A4 in the image space. The image cropping module 220 crops thesub-region R1 from the digital image I1 according to the control pointsA1˜A4. Please note that the touch screen 100 may display a previewversion of the digital image I1, which is of lower resolution. And theimage cropping module 220 may perform image cropping on the digitalimage I1 in full resolution. The image cropping module 220 also performsother modifications such as scaling and/or morphing on the croppedsub-region M to generate the sub-image C1. Specifically, the imagecropping module 220 may transform the sub-image C1 from anon-rectangular shape in the image space into rectangular shape in thecropping space.

Please refer to FIGS. 3 and 4, which illustrate an operation of imagecropping manipulation according to an embodiment of the invention. Asshown in the left of FIG. 3 and with reference to FIG. 2, the imagecopping module 220 generates a sub-image C2 cropped from a digital imageI2 and provides it for displaying on the touch screen 100 to the user.The digital image I2 is assumed to be in an image space and thesub-image C2 is assumed to be in a cropping space. The control pointsA1˜A4 define the sub-region R2 corresponding to the sub-image C2 in theimage space. User inputs received in the cropping space can be mapped tocorresponding operations in the image space by the space mapping module210. In this embodiment, the sub-image C2 initially does not fully coverthe object N in the digital image I2. User may send user inputs via thetouch screen 100 to update content of the sub-image C2. Since the mostleft part of object N is not shown, user may drag his/her finger fromleft to right on the touch screen 100 until the sub-image C2 is fullycovered by the object N, as shown in the right of FIG. 3. To update thecontent of the sub-image C2, the space mapping module 210 maps the draguser input in the cropping space to operations on the control pointsA1˜A4 in the image space. The control points A1˜A4 are moved from rightto left in relative opposite direction to the user input. In thisembodiment of the invention, the control points A1˜A4 are movedsynchronously. However, in other embodiments of the invention, each ofthe control points A1˜A4 may be adjusted independently.

FIG. 5 illustrates a space mapping mechanism according to an embodimentof the invention. The space mapping mechanism may be performed by thespace mapping module 210. In the cropping space where the sub-image C2lies in, a plurality of control regions T1˜T5 are defined. At least aportion of the control regions, in this embodiment T1˜T4, correspond tothe control points A1˜A4 in the image space respectively. For a givencontrol region, user inputs received in that region are mapped tooperations of corresponding control points. For example, user inputsreceived in control region T1 are mapped to operations of the controlpoint A1. By manipulation of user input in the control region T1, usermay change position of the control point A1 in the image space and thuschange content of the sub-image C2 nearby control region T1. For thecenter control region T5, user inputs received in this region would bemapped to all of the control points A1˜A4, causing them to movepositions synchronously.

Please note that, in the image space the control points A1˜A4 may notform a rectangular or square as the sub-image C2 does. As a result, themoving direction of the user inputs in each control region would beremapped to proper directions in the image space. The image space may beregarded as a vector space formed by the control points A1˜A4. Thecontrol point A1 may comprise four principal vectors with respect toother control pints A2˜A4. Vector V11 points from control point A1 toA3, vector V12 points from A2 to A1, vector v13 points from A3 to A1 andvector V14 points from A1 to A2. The drag user input in the controlregion T1 also forms an input vector, and the input vector is mapped toan output vector according to the vectors V11˜V14. Similarly, controlpoint A2 has principal vectors V21˜V24, and user inputs in the controlregion T2 are mapped to output vectors according to principal vectorsV21˜V24. Control point A3 has principal vectors V31˜V34, and user inputsin the control region T3 are mapped to output vectors according toprincipal vectors V31˜V34. And control point A4 has principal vectorsV41˜V44, and user inputs in the control region T4 are mapped to outputvectors according to principal vectors V41˜V44. For user inputs in thecontrol region T5, if the user input is in horizontal direction fromleft to right, as input vector D1, control points A1˜A4 should behorizontally from left to right accordingly. For example, control pointsA1 and A3 would move along principal vectors V11 and V31 accordingly.Similarly, if the user input is in vertical direction in the controlregion T5, control points A1 and A2 would move together along the vectorformed in-between and control points A3 and A4 would move together.

To better illustrate the movement of the control points in response touser inputs, several embodiments will be described in below. However,please note that the invention is not limited to these embodiments.Modifications or variations may be made without departing from thespirit of the invention. Please refer to FIGS. 6˜8, which illustrate anexample of user input received in a specific control region. As shown inleft of FIG. 6, a sub-image C3 is provided on the touch screen 100 tothe user. It can be observed that there exists large distortion at thetop-left region of the sub-image C3. In this case, user might wish torectify the distortion and bring in more contents. To achieve thispurpose, user may send a drag user input from the top-left corner of thecropping image C3 to an inner position. The drag user input in thecropping space is shown in the left of FIG. 7 and converted as inputvector D14. As shown in FIG. 7, the input vector D14 occurs in thecontrol region T1, and maps to an output vector V123 with respect tocontrol point A1 in the image space. Please note that the output vectorV123 is in relative opposite direction to the input vector D14. That is,when user drags from an outer position to inner position on the touchscreen 100, the attempt is to move the dragged content further insideand reveals uncovered outer contents. To include the previouslyuncovered contents, the control point has to extend further outside. Asa result, the input vector and the output vector point to oppositedirections.

Further explained, the input vector D14 is determined by the trace ofthe user input (for example start point and end point), and can bedefined by the combination of the principal vectors D1 and D4 in thecropping space. As can be understood, the cropping space is inrectangular shape with right angles. Thus, each vector in the croppingspace can be composed as a combination of two principal vectors, the twovectors form a right angle in between, for example D1 and D4 in FIG. 7.However, in the image space the control points X1˜X4 may not form arectangle or a square, the angles between the principal vectors may notbe right angles. Thus vector mapping should be performed to convert theinput vector in the cropping space (for example D14) to correspondingoutput vector in the image space (for example V123). The mapping can bedone by determining the ratio of a first angle between D14 and D1 (orD4) and a second angle between V123 and V13 (or V12). And the movingdistance of V123 can be mapped from the relative moving distance of D14.

In an embodiment of the invention, the control point X1 and thedisplayed cropping image C3 can be updated with the drag user input inreal-time. That is, when user places his/her finger on the touch screen,the sub-image C3 is updated along with finger movement. The user maystop dragging upon a desired cropping image C3 is disclosed. In thiscase, the control point X1 is updated with the finger movement as wellso that the sub-image C3 can be updated. Please note that the relativevectors V11˜V14 corresponding to vectors D1˜D4 may also be updated inresponse to the update of control point X1. In other words, when thecontrol point X1 moves its position, the axes form by the control pointsX1˜X4 would change accordingly. As a result, the pointing directions ofthe principal vectors V11˜V14 relative to control point X1 would change,and also does the output vector V123 in consequent.

FIG. 8 depicts image cropping in the image space. The sub-region R3corresponding to the control points X1˜X4 is cropped by the imagecropping module 220 and displayed as the sub-image C3 of FIG. 6. Thecontrol point X1 initially lies inside the object M desired to becropped. Upon receiving the drag user input from the user, the controlpoint X1 is moved to desired position, which is the top-left corner ofobject M, as shown in the right of FIG. 8. Please note that even thoughthe sub-region R3 appears in the digital image I3 in a non-rectangularshape, it is mapped into the cropping space in rectangle. Therefore,distortions appears at edge, corner or other portions in sub-region R3can be rectified in the sub-image C3, as shown in comparison of FIG. 6and FIG. 8. Pixel values and positions may be adjusted according to themovement of control points, and thus the scale and aspect ratio of thesub-image C3 is adjusted. In the condition that an object within animage is not taken in front view, by cropping and adjusting controlpoints of a sub-region according to the invention, the object can bepresented in front view for better view.

FIGS. 9, 10 and 11 illustrate another embodiment of image cropping ofthe invention. In this embodiment, the user interface is capable toreceive multiple drag user inputs corresponding to multiple controlpoints simultaneously. First please refer to FIG. 9, a sub-image C4 isprovided and displayed on a user interface for of the touch screen 100.The sub-image C4 corresponds to a sub-region R4 in the digital image I4and is defined by control points X1˜X4. As shown in the left of FIG. 10,the top-left and bottom-right portions of the digital image I4 are notcovered by the sub-region R4. To reveal those uncovered portions, theuser may use two fingers to drag from the top-left and bottom-rightcorners to the center simultaneously (FIG. 9). Corresponding controlpoints X1 and X4 would move outward in the top-left and bottom-rightdirections respectively (FIG. 10). As described above, the two userinputs are located in the control region T1 and T4 respectively and areconverted into two input vectors D14 and D67. The input vectors D14 andD67 are mapped into the image space as output vectors V123 and V414, butthe input vectors and the output vectors are of relative oppositedirections. The mapping of input vector D14 and the output vector V123is similar to the embodiment of FIG. 7. The mapping of D67 and V414 canbe done by determining the ratio of a first angle between D67 and D6 (orD7) and a second angle between V414 and V44 (or V41). And the movingdistance of V414 can be mapped from the relative moving distance of D67.

Please note that the user input may be a single input corresponding toone control point or multiple inputs corresponding to multiple controlpoints. In the latter case, the multiple inputs may correspond to anycombination of the control points, such as X1 and X4 in FIGS. 10 and 11,X1 and X2, or even X1, X2 and X3.

Please refer to FIG. 12. FIG. 12 illustrates an image croppingmanipulation method according to an embodiment of the invention. Theimage cropping manipulation method may be implemented in a portableelectronic device, such as a smart phone, tablet, and/or others. Theportable electronic device may comprise touch screen for displayingimages and providing a user interface to receive user inputs. Theportable electronic device may also comprise an image processing unitfor performing various image processing. Starting from step S1210, adigital image is displayed on the touch screen. The digital image can becaptured by a camera module of the portable electronic device or beaccessed from internal or external storage unit. Next the touch screenreceives a first user input corresponding to a sub-region of the digitalimage in step S1220. As mentioned, the touch screen may provide userinterface for receiving user inputs corresponding to various operations.In the embodiment of the invention, the user interface may compriseimage edit functions, such as rotate, crop, effect, etc. User may selecta desired function via the user interface, for example crop in thisembodiment. The user input may comprise information of a sub-region tobe cropped. In step S1230, the image processing unit of the portableelectronic device crops the sub region from the digital image andprovides a corresponding sub-image on the touch screen. Please note thatthe digital image displayed on the touch screen may be of previewresolution, which is lower than original resolution. The sub region maybe cropped from the digital image of full resolution, and be processedprior to generate the sub-image.

While viewing the sub-image, user may wish to apply further operationson the sub-image. The touch screen may also provide user interface forreceiving user inputs corresponding to operations on the sub-image. Forexample, the cropped sub-image may not be satisfying and the user wantsto modify the scope of the sub-image. In step S1240, the touch screenreceives a second user input for editing the sub-image. The user inputmay be a single-touch or multi-touch gesture, and comprise informationof position(s) user desires to modify. For example, user may apply adrag input moving from left to right to indicate that he/she wants tocrop a sub-region further left in the digital image to the currentlydisplayed sub-image. In another example, user may drag from one or morecorners of the sub-image to extend the sub-region broader in the digitalimage. Please note that user may directly send user inputs on thesub-image to modify its content without returning to the digital imagefor selecting a new sub-region to be cropped. In step S1250, the userinput is mapped to an operation on the digital image. In embodiments ofthe invention, the image processing unit defines an image spacecorresponding to the digital image and a cropping space corresponding tothe sub-image. The user input received from the touch screen in firstdetermined in the cropping space and converted to an operation in theimage space. That is to say, the actual operation takes place on thedigital image, however the user input is received on the sub-image. Aplurality of control regions corresponding to the sub-image aredetermined in cropping space, and a plurality of control pointscorresponding to the sub-region are determined in the image space. Userinputs fall in one or more of the control regions can be mapped toadjustment of one or more control points. The image processing unit mayconvert the user input to an input vector in corresponding controlregion, and map the input vector to an output vector with respect tocorresponding control point in the image space. In step S1260, the imageprocessing unit performs corresponding operation to update thesub-image. The control point is moved according to the output vector,leading to the adjustment of the sub-region. By adjusting the positionsof the control points, the sub-region is adjusted accordingly and thusthe sub-image is updated. Please note that the input vector and theoutput vector are of relative opposite direction. For example, if theinput vector points from left to right (i.e. user input is a drag fromleft to right), the output vector points from right to left (i.e.control point moves from right to left).

FIG. 13 illustrates another embodiment of image cropping manipulationmethod of the invention. Similar to the embodiment of FIG. 12, thisembodiment may be implemented in a portable electronic device comprisinga touch screen and an image processing unit. In step S1310, a sub-imageis displayed on the touch screen. The sub-image corresponds to asub-region cropped from a digital image. In step S1320, a user input isreceived from the touch screen. The touch screen may provide userinterface for receiving user inputs corresponding to various operationsto the sub-image. In step S1330, the image processing unit defines animage space corresponding to the digital image and a cropping spacecorresponding to the sub-image. Please note that step S1330 may beperformed prior to step S1320. In the image space, a sub-regioncorresponding to the sub-image is defined by a plurality of controlpoints. In the cropping space, a plurality of control regions isdefined. Each of the control regions corresponds to one or more of thecontrol points. In step S1340, the image processing unit maps the userinput from the cropping space to the image space. The image processingunit determines one or more control regions in which the user input isreceived. If the user input is a single-touch gesture, a correspondingcontrol region is determined. If the user input is a multi-touchgesture, control regions corresponding to the multi-touch aredetermined. The movement of the user input is converted to an inputvector in the corresponding control region. And the input vector is thenmapped to an output vector of the corresponding control point. In stepS1350, the image processing unit adjusts the sub-region in the imagespace according to the user input. The image processing unit adjusts thecontrol point according to the output vector, which is mapped andconverted from the user input. As described earlier, the sub-region isdefined by the control points. By adjusting positions of the controlpoints, the sub-region is adjusted accordingly and again cropped fromthe digital image. Then in step S1360, the sub-image is updatedaccordingly on the touch screen. Please note that the update of thesub-image may be performed synchronously with the receiving of the userinput. That is to say, the sub-image is updated along with the movementof the user input with minimum delay or without delay. Also, the userinput is directly applied during the display of the sub-image. Althoughoperations of the user input are performed on the digital image in imagespace, the user interface stays in the cropping space of the sub-image.Last in step S1370, the updated sub-image may be stored in storage unitof the portable electronic device or an external storage device. Forexample, user may store the sub-image in the memory of the portableelectronic device or upload the sub-image to a social media server.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A portable electronic device for performing imagecropping manipulation, comprising: a touch screen configured to displaya sub-image and to provide a user interface for receiving at least oneuser input, the sub-image is cropped from a digital image; and an imageprocessing unit, configured to perform an operation corresponding to theuser input, the image processing unit comprises: a space mapping module,configured to map the sub-image to an image space and map the user inputto the operation in the image space; and an image cropping module,configured to perform the operation and update the sub-image accordingto the user input.
 2. The portable electronic device of claim 1, whereinthe space mapping module is further configured to define the image spacecorresponding to the digital image and a cropping space corresponding tothe sub-image, and configured to map the user input from the croppingspace to the image space for adjusting a sub-region corresponding to thesub-image in the image space.
 3. The portable electronic device of claim2, wherein the space mapping module defines a plurality of controlpoints in the image space and a plurality of corresponding controlregions in the cropping space, and the space mapping module determinesat least a first control region where the user input is received andmaps the user input to an operation of at least a first control pointcorresponding to the first control region.
 4. The portable electronicdevice of claim 3, wherein the plurality of control points define thesub-region corresponding to the sub-image in the image space.
 5. Theportable electronic device of claim 3, wherein the space mapping moduleadjusts positions of the control points in the image space according tothe user input, and the image cropping module updates the sub-imageaccording to the adjusted control points.
 6. The portable electronicdevice of claim 2, wherein the user input is converted to an inputvector in the cropping space and mapped to an output vector in the imagespace, the input vector is in relative opposite direction to the outputvector.
 7. The portable electronic device of claim 1, furthercomprising: a camera module, configured to capture the digital image;and a storage unit, configured to store the digital image and thesub-image.
 8. The portable electronic device of claim 1, wherein theuser input is received without returning to display of the digitalimage.
 9. An image cropping manipulation method for use in a portableelectronic device, the portable electronic device comprises a touchscreen and an image processing unit, the method comprising: displaying asub-image on the touch screen, the sub-image is cropped from a digitalimage; receiving a user input from the touch screen; in response to theuser input, map the user input to an operation on the digital image; andperforming the operation to update the sub-image.
 10. The image croppingmanipulation method of claim 9, further comprising: defining an imagespace corresponding to the digital image and a cropping spacecorresponding to the sub-image; mapping the user input from the croppingspace to the image space; and adjusting a sub-region corresponding tothe sub-image in the image space according to the user input.
 11. Theimage cropping manipulation method of claim 10, wherein the mapping ofthe user input further comprises: defining a plurality of control pointsin the image space and a plurality of corresponding control regions inthe cropping space; determining at least a first control region wherethe user input is received; and mapping the user input to an operationof at least a first control point corresponding to the first controlregion.
 12. The image cropping manipulation method of claim 11, whereinthe plurality of control points define the sub-region corresponding tothe sub-image in the image space.
 13. The image cropping manipulationmethod of claim 11, wherein the determining of the sub-region furthercomprises: adjusting positions of the control points in the image spaceaccording to the user input; and updating the sub-image according to theadjusted control points.
 14. The image cropping manipulation method ofclaim 10, wherein the mapping of the user input further comprises:converting the user input to an input vector in the cropping space; andmapping the input vector to an output vector in the image space; whereinthe input vector is in relative opposite direction to the output vector.15. The image cropping manipulation method of claim 9, furthercomprising storing the updated sub-image.